This invention relates to attachments for back hoe buckets of vehicles, and more particularly, to an attachment including a fork lifting device.
There have been many attachments to buckets of vehicles, both front and back types of buckets, as shown by the following U.S. Pat. Nos.:
______________________________________ 2,421,472 Way 3,921,837 Vandewater 2,488,695 Upton 4,056,205 Etzler 2,577,977 Nelson 4,120,405 Jones et al 3,312,361 Foster 4,125,952 Jennings 3,421,642 Carter 4,172,687 Schultz 3,440,744 Smith 4,175,900 Etzler 3,665,622 Lamb 4,200,423 Sornsin 3,667,633 Cappella 4,242,035 Hornstein 3,706,388 Westendorf 4,247,243 Carter 3,749,262 Stark 4,275,985 Schremmer 3,807,802 Betters 4,329,103 Miller 3,812,979 Leihgeber 4,360,980 Jarvis ______________________________________
and by British Pat. No. 1,373,646.
The prior art attachments are often complex in design, expensive to manufacture and not readily installed and/or maintained. Often the entire attachment must be removed from the bucket to enable use of the bucket in the intended manner. These and other problems are believed to be substantially alleviated by the attachment according to the hereinafter disclosed invention.
SUMMARY OF THE INVENTION
The attachment for a back hoe bucket according to this invention includes a pair of elongated spaced support arms secured to and extending above respective side walls of the back hoe bucket adjacent the rear wall thereof, and each arm has an opening therethrough adjacent its upper end in substantial alignment with each other laterally of the bucket with each bottom wall forming the opening being generally flush with an upper edge of respective side wall of the bucket. An elongated upper bar extends laterally outwardly through the aligned openings in the arms and supported by the arms and adapted to be supported by the upper edge of the side walls of the bucket. A pair of elongated generally upright members each include lower and upper ends supported by the upper bar outboard of respective arms. Selective means releasably attach each of the upper ends of the upright members in selected lateral positions on the upper bar. An elongated lower bar extends substantially parallel to the upper bar, and means are provided to attach the lower bar to each of the upright members spacedly above the lower ends and generally below a back hoe bucket attachment to a boom of a back hoe vehicle to dispose the lower bar supportingly against a back wall of the bucket spaced adjacently above its bottom wall.
In other aspects the attachment in accord with this invention is provided with a pair of fork lift prongs respectively attached to the lower ends of the upright members and extend generally horizontally of the upright members. The means to attach the lower bar to each of the upright members may include a pair of support means carrying the lower bar and adjustable clamp means connected between respective support means and the upright member to selectively adjust the position of each of the support means along respective upright members. The upright members may have elongated slots with the clamp means including a pair of threaded bolts passing through respective support means and the lower bar and the upright member through the elongated slot and a pair of nut fasteners threadedly engaged on the bolts to releasably affix the lower bar in selected positions along the slots. The means to attach the lower bar to each of the upright members includes a clamp means slideable on each of the upright members, means to releasably affix the clamp means to the upright members, and support means carried by the clamp means for supporting the lower bar. The clamp means includes a hollow box element and the means to releasably affix the clamp means includes a set screw threadedly engaged with one wall of the box element with an inner end of the set screw selectively engaging the upright member passing through the hollow box element. Each support means carried by the clamp means may include at least one plate extending laterally of each box element between the upright member and the back wall of the bucket, and the one plate has an opening through which the lower bar extends. Each support means may also include another substantially identical plate extending laterally of each box element and parallel to the one plate.
In yet other aspects, the attachment according to this invention is seen to include releasable means for securing each of the spaced support arms to respective side walls of the bucket, the releasable means including a first bolt and nut fastener passing through and fastened about a first opening in each support arm below the opening receiving the upper bar in the upper end of the arm, and an aligned opening in the bucket, and a second bolt and nut fastener passing through and fastened about an arcuate slotted second opening in each support arm below the first opening and another aligned opening in the bucket generally located centrally of the second opening to permit angular adjustment of the support arms about the first bolt and nut fastener.
Further aspects in accord with this invention are directed to the provision of the selective means to releasably affix each upright upper end to the upper bar includes a set screw threadedly engaged with the upright upper end and engaging the upper bar. In an alternate embodiment each selective means includes a bolt and nut fastener passing through and secured to respective upright member and the upper bar. Each upright member includes a hollow box element forming each upper end thereof with the upper bar passing through the hollow of respective box element, the nut and head of the bolt engaging on opposite side walls of the box element with the bolt passing through the opposite side walls and the upper bar.
Additional aspects are provided to the attachment according to this invention wherein each upright member includes a hollow box element forming each upper end thereof with the upper bar passing through the hollow of respective box element. Each selective means is engaged on the box element and engages the upper bar. The selective means includes a set screw threadedly engaged with one wall of the box element and engaging the upper bar internally of the box element. The upper bar may be hollow and may conform in shape to the hollow box element with such shapes being complementary and are substantially square. Therefore the lower bar may be substantially square and each of the means to attach the lower bar to each of the upright members includes a pair of support means having a substantially square opening receiving the square lower bar. The lower bar may be substantially round and each of the means to attach the lower bar to each of the upright members includes a pair of support means having a substantially round opening receiving the round lower bar.
The principal object of this invention is to provide an attachment to a back hoe bucket to be employed to load and unload pipe from trucks without detaching the bucket.
Another object of this invention is to provide an attachment which is adaptable to also string pipe, and does not use chains, which are dangerous when applied to P.V.C. pipes to inhibit slippage.
Another object of this invention is to provide an attachable fork lifting device, which will be of such design, as to require only one man to perform the task of loading and unloading pipe.
A further object of this invention is to provide a fork lifting attachment, which will be removably supported on the bucket portion of the back hoe vehicle.
A still further object of this invention is to provide a fork lifting attachment which will be easily adjustable to handle various lengths of pipe, as long as twenty feet, safely.
Other objects of the invention are to provide a fork lifting attachment which will be simple in design, inexpensive to manufacture, rugged in construction, and easy to install and maintain.